Major texts state that the human symptoms of the disease Opisthorchiasis
was first described in 1875. In 1884, the parasite Opisthorchis felineus
was first discovered in cat liver in Northern Italy. In 1891 a Russian
scientist, K. N. Vinogradov discovered this parasite in a human and
named it the "Siberian liver fluke."

Opisthorchis viverrini is the only parasite that causes Opisthorchiasis
in the heavily infected area of Thailand. The first case of Opisthorchiasis
in Thailand was discovered in 1911 through autopsy.